Income Taxes, (As Restated for fiscal 2014 and 2013) - Summary of Components of Company's Income Tax Provision (Benefit) from Continuing Operations (Details) - USD ($) $ in Millions	3 Months Ended							6 Months Ended		9 Months Ended		12 Months Ended
	Aug. 31, 2015	May. 31, 2015	Feb. 28, 2015	Nov. 30, 2014	Aug. 31, 2014	May. 31, 2014	Feb. 28, 2014	May. 31, 2015	May. 31, 2014	Aug. 31, 2015	Aug. 31, 2014	Nov. 30, 2015	Nov. 30, 2014	Nov. 30, 2013
Current
U.S. federal												$ 33.0	$ 19.0	$ 1.8
State and local												3.4	4.1	1.0
Current income tax provision (benefit)												36.4	23.1	2.8
Deferred
U.S. federal												(41.2)	(5.5)	(150.3)
State and local												5.1	(1.3)	(50.9)
Deferred income tax provision (benefit)												(36.1)	(6.8)	(201.2)
Income tax provision (benefit)	$ (21.7)	$ 19.9	$ (5.8)	$ 14.6	$ (0.5)	$ 0.2	$ 2.0	$ 14.1	$ 2.2	$ (7.6)	$ 1.7	$ 0.3	$ 16.3	$ (198.4)